#include <iostream>
#include <stdlib.h>

using namespace std;
int main(){
    cout<<"this is a C++ program!\n";
    int a=10;
    int &b=a;
    cout<<a<<" "<<b<<endl;
    a=a*a;
    
    cout<<a<<" "<<b<<endl;
    b=b/5;
    cout<<a<<" "<<b<<endl;
    system("pause");
    return 0;
}
